Incandescent electric lamp



(No Model.)

W. E. NIOKERSON. INGANDBSGENT ELECTRIC LAMP.

No. 503,670. Patented Aug, 22, 1893.

UNITED STATES PATENT OFFICE.

WILLIAM EMERY NIOKERSON, OF CAMBRIDGE, MASSACHUSETTS.

INCANDESCENT ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 503,670, dated August 22, 1893.

Application filed July 19, 1893- Serial No. 430,930. (No model.)

To all whom it may concern.-

Be it known that 1, WILLIAM EMERY NICK- ERSON, of Oambridge,in the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in Incandescent Electric Lamps, of which the following, taken in connection with the accompanying drawing, is a specification.

My invention relates to that class of incandescent electric lamps, in which the neck of the lamp bulb is closed air-tight, and the leading-in wires sealed and supported, by a plug of fusible cement. Its object is to prevent the breaking of the perfect contact of the wires with the cement which might otherwise occur as the result of handling during manufacture.

My invention is illustrated in the accompanyingdrawings, in which- A is the glass bulb of an incandescentlam p, the neck of which is adapted to be closed airtight by the plug of fusible cement B. The latter is supported when soft by the disk of mica O, which rests upon the shoulder D formed in the neck of the lamp bulb.

E E are the leading-in wires to which the filament F is attached atE E. The leadingin wires E E are provided with the bends E E located above, but not in contact with,the disk 0, and within the body of the cement plug 13. A base or cap G, of an ordinary kind, is secured to the top of the lamp neck in the usual manner, by plaster of paris. The ends of the leading-in wires are attached by soldering to the perspective parts G G of the cap, in order to properly complete the electric circuit when the lamp is placed in its socket.

My invention relates to the bends E E in the leading-in wires E E. These bends are an effectual remedy for a defect which, when they are not used,frequently im pairs the value of lamps of the class described in this specification, and which may be explained in the following manner.

Ordinarily the leading-in wires offer but little surface for the adhesion of the cement through which they pass. Insomuch, that break their perfect mechanical contact with the cement, and spoil the lamp by causing it to leak. The bends E E which are located Within the cement, and preferably near the upper surface, prevent the breaking of the perfect contact of the cement with that part of each wire which lies between the bends and the disk 0. This is accomplished by the resistance which the bends offer to being forced through the cement, either by pushing, pulling or twisting. Hence a perfect union of surfaces is preserved, in a part at least, of the immersed portion of the wires, and leakage is thereby prevented.

Instead of bonds, buttons of metal, glass, or other suitable material, may be attached to the wires, which would also tend to prevent them from moving in the cement, and thereby breaking the perfect mechanical contact.

In my Patent No. 500,076, granted June 20, 1893, for an incandescent electric lamp, bends in the leading-in wires are shown located at the inner surface of the cement plug by which the neck of the lamp is closed. They rest on the disk which supports the cement plug, and are in contact with it. Their purpose is to prevent the wires from dropping into the lamp, before the cement plug has become fixed in" its place during manufacture. They would not perform the function of the bends described in this specification, since, as they are in contact with the disk and at the inner surface of the cement plug, there is no portion of the wires immersed in the cement, which would be protected by their use, as all that part of the Wires located above them within the cement, would be subject to movement, owing to their flexibility, whereby the contact of the cement with the wires might be broken, even to the inner surface,causing leakage. While the bends in Patent No. 500,076 are located adjacent to and in contact with the cementsupporting disk and at the inner surface of the cement plug for the purpose of preventing the wires from slipping into the lamp during manufacture, the bends described in this specification are located within the cement at a distance from the disk, leavinga portion of protected wire between them and it, and are for the purpose of preventing such portion of protected wire, from being moved in tnecement, by pulling, pushing or twisting, and prevent thereby, leakage of air into the lamp.

The gist of my invention consists in bends or their equivalent in connection with the leading-in wires of an incandescent electric lamp of the class described, said bends being so placed within the cement by which the neck of the lamp bulb is closed, that they prevent that part of the wires which is located between them and the inner surface of the cement from breaking the perfect contact with the cement, and thereby preventing leakage.

I claim- 1. In an incandescent electric lamp in which the neck of the lamp bulb is closed air-tight by a plug of fusible cement, bends in the leading-in wires, located within the cement plug but not at its inner surface and adapted to prevent the said wires from breaking their perfect mechanical contact with the said cement, substantially as and for the purpose set forth.

2. In an incandescent electric lamp, the combination of the glass bulb A havinga neck adapted to be closed air-tight by a plug of fusible cement, the plug of fusible cement B, the filament F, and the leading-in wires E E, said wires being provided with the bends E E located within the cement plug B, but not at its inner surface and adapted to prevent the wires E E from breaking their perfect mechanical contact with the cement, substantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing Witnesses, on this 17th day of July, A. D. 1893.

WILLIAM EMERY NICKERSON.

Witnesses:

FRANK G. PARKER, FRANK G. HA'ITIE. 

